The only chance to see a 2.6 running on your Zaurus before the hardware gets hopelessly outdated and uninteresting, is to find more people joining John Lenz.
That said, since there doesn't seem that much people interested in even doing trivial stuff like maintaining packages or so for the Zaurus, I don't really expect to see kernel guys joining us.
At the recent LinuxWorldExpo in London last week, many of us got the chance to meet part of the emdebian team who were exhibiting all kinds of embedded devices happily running debian.
One of the showstoppers of the day for me (and many others) was a prototype version of the Psion Netbook PRO. This machine normally ships with Windows CE via Psion who aim the product at Business users in vertical markets (i.e. Stock control, medical etc).
Also exhibiting at the expo were a company called Xios, who have been working to market the Netbook PRO to corporate clients and business users, as a replacement for a laptop.
As part of this marketing bid, they have decided to base their OS on Linux and make the entire thing appeal to developers as well as corporate users. On display was a Netbook PRO happily running the 2.6.9 kernel and a rather fetching new GUI called the "Xios Desktop" iirc.
The magic of shoehorning the 2.6 kernel onto the psion was done by many of the emdebian team, who were contracted by Xios to do the work. What you're left with is a very capabable piece of hardware with a very nice looking OS.
I would not like to imagine how much it cost to contract the Kernel development work out to these talented kernel developers, although from the results it seems it was worth every penny. (The Xios marketing people were very excited about the response the machine was getting)
Unfortunately for us Z users/developers, we don't even have the corporate marketing backing of Sharp most of the time so I would be very suprised to see any Kernel bods working on the Z any time soon, unless they used the hardware or were paid to do so.